Quantum backflow for many-particle systems

Abstract

Quantum backflow is the classically-forbidden effect pertaining to the fact that a particle with a positive momentum may exhibit a negative probability current at some space-time point. We investigate how this peculiar phenomenon extends to many-particle systems. We give a general formulation of quantum backflow for systems formed of $N$ free nonrelativistic structureless particles, either identical or distinguishable. Restricting our attention to bosonic systems where the $N$ identical bosons are in the same one-particle state allows us in particular to analytically show that the maximum achievable amount of quantum backflow in this case becomes arbitrarily small for large values of $N$.

12 pages, 2 figures

References in corpus (2)

• Decay of a quasi-stable quantum system and quantum backflow
• Equivalence between quantum backflow and classically forbidden probability flow in a diffraction-in-time problem